p0300 03 silverado 4.8
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p0300 03 silverado 4.8
Recently my truck has been sitting a lot more than normal and the other day i jumped in it to head to a buddys house when the check engine light came on. P0300 random and multiple misfires. as well as p0455 large evap leak. well ive tried everyhting i can think of and still no luck fixing this problem. Runs righ at idle and as soo as you rev up engine like starts flashing. Any help would be appreciated
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the large evap leak has nothing to do with the misfire condition so ignore it for now.
even though random misfires dtc are set, if you have access to a scan tool with misfire data...view the data to see which cylinders are misfiring.
misfiring at high rpm can be from:
-bad coils, plugs, plug wires
-low fuel pressure
-exhaust restriction/clogged cats
I would start by checking fuel pressure.
even though random misfires dtc are set, if you have access to a scan tool with misfire data...view the data to see which cylinders are misfiring.
misfiring at high rpm can be from:
-bad coils, plugs, plug wires
-low fuel pressure
-exhaust restriction/clogged cats
I would start by checking fuel pressure.
Last edited by tech2; Jul 8, 2016 at 1:49 PM. Reason: missing words
